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CVE-2026-40257

OP-TEE has SHA-3 accelerated finalize heap overflow

Published: Jul 6, 2026Updated: Jul 7, 2026 Sources: CVE List NVDCWE-787
5.5MEDIUM
NVD MITRE
EPSS Score
0.1%
Top 98.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Workaround Only
Self-Check
Not available

Description

OP-TEE is a Trusted Execution Environment (TEE) designed as companion to a non-secure Linux kernel running on Arm; Cortex-A cores using the TrustZone technology. Starting in version 3.21.0 and prior to version 4.11.0, the ARM Crypto Extensions accelerated SHA-3 implementation has an off-by-one error that can cause a massive heap overflow that corrupts all TEE kernel memory following the hash state. This affects all platforms built with `CFG_CRYPTO_WITH_CE82=y` (ARMv8.2+ with SHA3 Crypto Extensions). Version 4.11.0 contains a patch. As a workaround, disable SHA3 Crypto Extensions with `CFG_CRYPTO_WITH_CE82=n`.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:LAC:LPR:LUI:NS:UC:NI:NA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-787

Affected Products

trustedfirmware
commercialaka mbed tls, op-tee, trusted firmware-a
op-teeOn-prem
Security Products / pki-crypto
OP-TEE
oss-projectaka optee, op-tee os
optee_osEmbedded
Operating Systems / rtos-embedded-os

Exploitability

Workaround Available

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://github.com/OP-TEE/optee_os/security/advisories/GHSA-75x4-j8p9-55qv
github.com

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